Wireless ultra wideband network having frequency bin transmission level setting and related methods

ABSTRACT

A wireless ultra wideband (UWB) network may include a plurality of UWB wireless devices communicating over a plurality of UWB frequency bins extending over a UWB frequency range. At least one of the UWB wireless devices may be for determining an existing interference level associated with at least one of the UWB frequency bins, and for setting a desired transmission level for use with the at least one UWB frequency bin. In particular, the desired transmission level may be set based upon the existing interference level to keep a predicted overall interference level of the at least one UWB frequency bin below an interference ceiling.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application Nos.60/539,684, and 60/539,683, both filed Jan. 28, 2004, which are herebyincorporated herein in their entireties by reference.

FIELD OF THE INVENTION

The present invention relates to the field of wireless communicationssystems, and, more particularly, to wireless ultra wideband (UWB)communications systems and related methods.

BACKGROUND OF THE INVENTION

Ultra wideband (UWB) is currently expected to become the preferredformat for wireless communications in certain short range applications,such as personal area networks (PANs), for example. By way of example, aPAN may include a number of household electronic devices such as videorecorders, personal computers, high-definition televisions (HDTVs),etc., which communicate video, audio, and other data therebetween. UWBtechnology is particularly attractive for PANs not only because itallows large amounts of digital data to be transmitted over a shortdistance at very low power, but it also has the ability to carry signalsthrough obstacles (doors, etc.) that otherwise tend to reflect signalsat narrower bandwidths and higher power.

As a result of the significant interest in UWB communications, anInstitute for Electrical and Electronic Engineering (IEEE) working grouphas been tasked with developing standards for UWB communications inwireless PANs. In particular, the IEEE802.15.3a working group isdeveloping a high-speed UWB physical layer (PHY) enhancement to thegeneral 802.15.3 WPAN standard for applications which involve imagingand multimedia.

One of the leading UWB waveforms in the IEEE802.15.3a selection processis frequency hopping orthogonal frequency division multiplexing(FH-OFDM). While much progress has been made in developing the frameworkfor FH-OFDM, many areas remain to be fully developed. One such area isinterference mitigation. In one proposal submitted Nov. 10, 2003 byBatra et al. entitled “Multi-band OFDM Physical Layer Proposal for IEEE802.15 Task Group 3a,” which is hereby incorporated herein in itsentirety by reference, the use of a front-end pre-select filter in UWBreceivers is proposed to reject out-of band noise and interference.

Other interference mitigation techniques have also been proposed for UWBcommunications. By way of example, U.S. Pat. No. 6,560,463 to Santhoffdiscloses a UWB communication system which includes a transceiverconfigured to receive a UWB communication signal, which has embeddedpower level data. A measurement circuit in the transceiver measures thestrength of the received signal. An attenuation factor is computed thatcompares the measured signal strength to the data embedded in thesignal. An adaptive circuit uses the attenuation factor to select apower level for a next transmission. The transceiver also has apositioning circuit that is used to accurately determine the distancefrom the transceiver to the source of the communication signal, and theadaptive circuit uses the distance to tune the power level for the nexttransmission. This patent states that the accurate selection of thelowest acceptable power level minimizes interference betweencommunication cells, thereby increasing reliability and optimizingbandwidth utilization.

Despite the advancements in UWB communications, further improvements maybe required, such as for implementing the IEEE 802.15 standards. Thismay be particularly true in the area of interference mitigation.

SUMMARY OF THE INVENTION

In view of the foregoing background, it is therefore an object of thepresent invention to provide a UWB wireless network providing enhancedtransmission level setting features based upon existing interferencelevels and related methods.

This and other objects, features, and advantages in accordance with thepresent invention are provided by a ultra wideband (UWB) wirelessnetwork including a plurality of UWB wireless devices communicating overa plurality of UWB frequency bins extending over a UWB frequency range.At least one of the UWB wireless devices may be for determining anexisting interference level associated with at least one of the UWBfrequency bins, and setting a desired transmission level for use withthe at least one UWB frequency bin. In particular, the desiredtransmission level may be set based upon the existing interference levelto keep a predicted overall interference level of the at least one UWBfrequency bin below an interference ceiling.

More specifically, the existing interference level may be aninterference noise temperature level, and the interference ceiling maybe an interference noise temperature ceiling. Thus, the transmissionlevel for one or more frequency bins may advantageously be individuallyset to a maximum level that will still keep the overall interferencenoise temperature level under an interference noise temperature ceiling.

The UWB wireless device may determine the existing interference noisetemperature level by determining a plurality of successive signal levelsassociated with the at least one UWB frequency bin, determining aninterference noise floor based upon the successively determined signallevels, and determining the interference noise temperature level basedupon the interference noise floor. Moreover, the UWB wireless device maydetermine the interference noise floor by generating a histogram basedupon the successively determined signal levels, and determining theinterference noise floor based upon the histogram.

In addition, the UWB wireless device may have a gain level and a noiselevel associated therewith. As such, the UWB wireless device maydetermine the existing interference noise temperature level based uponthe interference noise floor and the gain and noise levels associatedwith the UWB wireless device. The UWB wireless device may include a fastFourier transform (FFT) module and/or a discrete Fourier transform (DFT)for determining the successive signal levels, for example.

The UWB wireless device may also communicate the desired transmissionlevel to another UWB wireless device for use in communicationstherewith. It may further determine the existing interference level whenit is not communicating with another UWB wireless device. By way ofexample, the UWB frequency bins may be orthogonal frequency divisionmultiplexing (OFDM) frequency bins, and the at least one UWB wirelessdevice may perform frequency hopping.

A UWB wireless communications method aspect of the invention may includeusing a plurality of UWB wireless devices to communicate over aplurality of UWB frequency bins extending over a UWB frequency range.The method may further include determining an existing interferencelevel associated with at least one of the UWB frequency bins, andsetting a desired transmission level for use with the at least one UWBfrequency bin based upon the existing interference level to keep apredicted overall interference level of the at least one UWB frequencybin below an interference ceiling.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is schematic block diagram of a UWB wireless network inaccordance with the present invention.

FIG. 2 is a more detailed schematic block diagram of the UWB devicecontroller as shown in FIG. 1.

FIG. 3 is a graph of a UWB channel with sub-bands and frequency binstherein illustrating signal levels exceeding a first threshold when thebins are not in use in accordance with the present invention.

FIG. 4 is a graph of the UWB channel of FIG. 3 and frequency binstherein illustrating signal levels exceeding a second threshold when thebins are in use in accordance with the present invention.

FIG. 5 is a diagram of a prior art UWB media access layer (MAC)superframe.

FIG. 6 is a signal flow diagram of the communication of a do-not-usefrequency list between UWB devices in accordance with the presentinvention.

FIG. 7 is a schematic block diagram of another UWB wireless network inaccordance with the present invention.

FIG. 8 is a more detailed schematic block diagram of the UWB devicecontroller as shown in FIG. 7.

FIG. 9 is a histogram of the OFDM bin energy for use in determining anexisting interference noise temperature in accordance with the presentinvention.

FIGS. 10 and 11 are flow diagrams for generating UWB frequency bindo-not-use lists in accordance with the present invention.

FIGS. 12 and 13 are flow diagrams illustrating methods for setting UWBfrequency bin desired transmission levels to keep an interference levelof the frequency bin below an interference ceiling in accordance withthe present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will now be described more fully hereinafter withreference to the accompanying drawings, in which preferred embodimentsof the invention are shown. This invention may, however, be embodied inmany different forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art. Likenumbers refer to like elements throughout, and prime notation is used toindicate similar elements in alternate embodiments.

Referring initially to FIG. 1, a ultra wideband (UWB) wireless network30 in accordance with the present invention illustratively includes aplurality of UWB wireless devices 31 a-31 n communicating over aplurality of UWB frequency bins extending over a UWB frequency range. Byway of background, the frequency range approved for UWB communicationsby the FCC in the U.S. extends from 3.1 GHz to 10.59925 GHz. Theproposed IEEE 802.15.3 multi-band UWB approach involves sub-dividingthis 7.5 GHz spectrum width into several 528 MHz sub-bands. Thesub-bands are grouped into five logical channels, some of which will bemandatory for all UWB devices, while others will be optional.Furthermore, for the proposed FH-OFDM structure, each sub-band isfurther sub-divided into 128 4.125 MHz OFDM frequency bins, giving atotal of 1818 bins which are numbered 0 through 1817.

During normal operation, the devices 31 a-31 n illustratively includerespective antennas 33 a-33 n, and these devices establish UWBcommunications links between one another and communicate via these linksin accordance with the appropriate UWB standards, such as those outlinedin the 802.15.3 and 3a proposals, for example. These devices thencommunicate accordingly over some grouping (e.g., a channel) of theabove-noted UWB frequency bins, as will be appreciated by those skilledin the art.

More particularly, the UWB device 31 a illustratively includes a UWBtransceiver 32 and associated antenna 33 a, and a controller 34 coupledto the UWB transceiver. It should be noted that the other UWB devices 31may include similar components, which are not shown for clarity ofillustration. In an FH-OFDM device, the controller 34 will preferablyinclude a fast Fourier transform (FFT) module 35 that can be used toperform a spectral scan across the frequency bins of the sub-band(s) ofinterest in a manner similar to a spectrum analyzer. A discrete Fouriertransform (DFT) module may also be used, as will be appreciated by thoseskilled in the art.

In accordance with the present invention, the FFT module 35 isadvantageously used to determine a respective actual signal levelassociated with each UWB frequency bin of interest (i.e., in the UWBchannel(s) or sub-bands being used). The controller 26 alsoillustratively includes a list generating module 36, which generates ado-not-use UWB frequency bin list by comparing each actual signal levelwith at least one interference threshold. By way of example, the FFTmodule 35 and the list generating module 36 may be implemented assoftware modules to be executed by a processor, as will be appreciatedby those skilled in the art.

In the case where the controller 34 and transceiver 32 operate usingFH-OFDM, the frequency of narrowband interference can advantageously beidentified to within the FFT accuracy of one OFDM bin. Thus, the UWBwireless devices 31 a-31 n (or at least some of these devices) can avoidusing those frequency bins experiencing excessive interference tothereby provide more reliable UWB communications.

The determination of the actual signal levels will be further understoodwith reference to FIGS. 3 and 4, each of which illustrates a UWB channelincluding three sub-bands. At each frequency hop, the FFT module 35determines which frequency bins are experiencing interference energy bycomparing the actual, measured signal level for that bin with one of twointerference thresholds. More particularly, when the frequency bin isnot in use, then a first interference threshold is used, as seen in FIG.3. In the illustrated example, the first sub-band, which is centered at3,342 MHz, has a bin with a signal level above the first interferencethreshold, as represented by the arrow 40. The second and thirdsub-bands, which are centered at 3,690 and 4,488 MHZ, respectively, alsohave frequency bins with signal levels above the first threshold, asrepresented by the arrows 41, 42.

The first interference threshold is preferably an expected averageenergy value for when no transmissions are occurring over the givenfrequency bin. As seen in FIG. 4, a second threshold, which is higherthan the first threshold, is used when the particular frequency bin inquestion is in use. The second threshold may similarly be an expectedaverage energy value for when a frequency bin is in use. It should benoted that other interference thresholds beside average values may beused, as will be appreciated by those skilled in the art. For example,the first and second interference thresholds may simply be maximumallowable or desired thresholds.

The monitoring/scanning of the UWB frequency range of interest may beaccomplished by observing link activity within the UWB media accesscontrol (MAC) superframe. Referring more particularly to FIG. 5, theIEEE 802.15.3 MAC superframe is a representative packet link superframe.This superframe includes three main periods, namely a beacon period, acontention access period (CAP), and a channel time allocation period(CTAP). A piconet controller (PNC) transmits beacons at the beginning ofevery superframe during the beacon period, and new UWB wireless devicesjoin a piconet during each CAP. The beacon period is used to set thetiming allocations and to communicate management information for thepiconet. The beacon consists of the beacon frame, as well as anyannounce commands sent by the PNC as a beacon extension.

The CAP is used to communicate commands and/or asynchronous data if itis present in the superframe. The CTAP is composed of channel timeallocations (CTAs), including management CTAs (MCTAs). CTAs are used forcommands, isochronous streams and asynchronous data connections. In FIG.5, the MCTAs are shown first, but the PNC is allowed to place any numberof them at any position in the superframe.

The length of the CAP is determined by the PNC and communicated to thedevices in the piconet via the beacon. However, the PNC is able toreplace the functionality provided in the CAP with MCTAs, except in thecase of the 2.4 GHz PHY where the PNC is required to allow devices touse the CAP. MCTAs are a type of CTA that are used for communicationsbetween the devices and the PNC. The CAP uses CSMA/CA for the mediumaccess. The CTAP, on the other hand, uses a standard TDMA protocol wherethe devices have specified time windows. MCTAs are either assigned to aspecific source/destination pair and use TDMA for access, or they areshared CTAs that are accessed using the slotted aloha protocol, as willbe appreciated by those skilled in the art.

The UWB device 31 a preferably monitors a particular UWB frequency rangefor narrowband interference activity during those periods when it is notcommunicating with other devices (i.e., when the PNC is not in use), forexample. Once the list generating module determines the frequency binswhich have an actual signal level above the appropriate threshold, itlogs an 11-bit binary value for each of the 1,818 frequency bins that issuffering interference. By way of example, suppose that interferenceactivity is observed at 4.7 GHz, between 5.20 GHz to 5.22 GHz and at 7.3GHz. If this interference maps to bins 388, 509, 510, 511, 512, 513, 514and 1018, then the list generating module 36 would generate and store ado-not-use frequency bin list including each of these bin numbers.

The UWB wireless device 31 a then communicates the table to one or moreother devices in the network 30, which also stores the list. Then, whenthese devices communicate with one another, they will not use thosefrequencies included in the stored list (unless this feature isdisabled, as will be discussed further below). Of course, the list maybe updated at periodic or intermittent intervals, or when a measuredquality-of-service (QoS) level indicates that a new list needs to begenerated, for example, as will be appreciated by those skilled in theart. It should also be noted that other devices in the network 30besides device 31 a may also generate do-not-use frequency bin lists asdescribed above in certain embodiments, if desired.

Referring more particularly to FIG. 6, to accommodate exchange of thedo-not-use frequency bin list between different devices 31, anadditional command (DNU List Command) may be introduced into the MACcommand structure for requesting that the do-not-use list be sent. Oncethis command is received, the receiving device (device B in theillustrated example) returns an acknowledge (ACK) command back to deviceA. Device B then sends the do-not-use frequency bin list to device A,which returns an ACK list receipt to device B. This notifies device Bthat the table was correctly received based, for example, on a correctcyclic redundancy check (CRC) checksum, as will be appreciated by thoseskilled in the art.

One further MAC modification which may be implemented in certainembodiments is to allow use of the do-not-use frequency bin list to besuspended. One way to do this is to add a bit to each transmitted packetheader to let the receiving device know whether the list is to be used(e.g., 0 indicates that the list is not to be used, 1 indicates that itis to be used, or vice-versa). An example of when it may not bedesirable for the transmitting device to use the list is in a multi-castenvironment where there is more than one receiver.

In certain applications, it may be desirable to use a template ordefault do-not-use frequency bin list as a starting point. For example,this might be done to tailor the UWB spectrum to meet a unique regionalregulatory frequency requirements. This may be accomplished by loadingthe template into the PHY information management data base. The defaulttemplate would be read prior to all transmissions and would be common toall devices within the piconet. Thus, the use of the do-not-use bit inthe header noted above could be restricted to making command changes tothe do-not-use frequency list during link time. This would allow thetransmitting device to adaptively adjust the spectrum for dynamicinterference environments, as will be appreciated by those of skill inthe art.

A wireless ultra wideband (UWB) communications method aspect of theinvention will now be described with reference to FIG. 10. The methodbegins (Block 100) with using a plurality of UWB wireless devices 31 tocommunicate over a plurality of UWB frequency bins extending over a UWBfrequency range, as discussed above, at Block 101. A respective actualsignal level associated with each UWB frequency bin is then determined,at Block 102, and a do-not-use UWB frequency bin list is then generatedby comparing each actual signal level with at least one interferencethreshold, at Block 103, as further discussed above, thus concluding theillustrated method (Block 104).

Further method aspects will now be described with reference to FIG. 11.Prior to determining the actual signal levels, the UWB wireless device31 a may first determine whether it is engaged in communications withanother device, at Block 110′. If so, it will wait until thecommunications are completed to begin the actual signal leveldetermination process. An initial determination is made as to whetherthe particular frequency bin is in use, at Block 111′, which may be doneon an individual basis, or at the sub-band or channel level, dependingthe particular implementation. If the frequency bin is not in use, thefirst threshold is used for comparison, at Block 112′, otherwise thesecond (higher) threshold is used, at Block 113′, as discussed above.Again, once generated the do-not-use frequency list is preferablycommunicated to one or more other devices for use in communicationstherewith.

Another related aspect of the invention will now be described withreference to FIGS. 7 and 8. Generally speaking, in the illustrated UWBnetwork 30′ the UWB wireless device 31 a′ determines an existinginterference level, such as interference noise temperature, associatedwith one or more of the UWB frequency bins. The device 31 a′ then sets adesired transmission level for use with the UWB frequency bin(s) basedupon the existing interference level to keep a predicted overallinterference level of the at least one UWB frequency bin below aninterference ceiling. By way of example, the interference level may bean interference noise temperature ceiling mandated by a governingauthority, such as the FCC. The device 31 a′ therefore advantageouslydetermines the maximum amount of transmission power that may be used fora given bin(s), yet still remain within regulatory guidelines tomaximize transmission capacity.

As noted above, an FH-OFDM device can perform a spectral analysis of theUWB channel during “dead time” when it is not actively participating indata transfer with another device. The spectral analysis is accomplishedby monitoring and measuring the energy in each OFDM bin. In accordancewith this aspect of the invention, enough measurements of the signallevel in each bin are taken to extract the interference noise floor ateach OFDM frequency bin. This can be done by taking multiplemeasurements and constructing a numerical histogram of energy in eachfrequency bin, which may be done by an interference noise temperaturemodule 80′.

An exemplary histogram is shown in FIG. 9. At any given time, afrequency bin will either have UWB transmissions therein, or it willhave only residual interference noise. The histogram may be used toseparate these two cases. Preferably, a separate numeric histogram isgenerated for each frequency bin (although all bins need not bemonitored in all applications), and thus 1,818 histograms will becreated. Again, each histogram is generated based upon multiple spectralmeasurements.

In the illustrated histogram it may be seen that the signal energy isbifurcated into two segments, namely an upper segment 90 whichrepresents an active UWB signal, and a lower segment 91 that representssome residual interference noise floor. In those cases where there is noUWB energy present during the generation of the histogram, only thelower segment would be present. The power in the lower segment 91 isused to determine the noise floor.

By knowing the variance of the lower segment 91 data, the receiver gainof the transceiver 32′ at the time that the histogram was generated, thereceiver noise figure of the transceiver, and by having an estimate ofthe antenna 33′ gain characteristics, the interference noise level canbe accurately estimated, as will be appreciated by those skilled in theart. Hence, the interference noise temperature that exists at a givenparticular frequency bin may also be estimated. Again, this informationis preferably ascertained for each 4.125 MHz wide frequency bin acrossthe UWB spectrum, although this need not be the case in all embodiments.

The interference noise temperature data generated as described above maybe stored in a column of a table with 1,818 rows (i.e., one row for eachfrequency bin). Another column in the table may include the applicableFCC-imposed interference noise temperature. The difference between thesevales is used to calculate a maximum allowable TX power, on a perfrequency bin basis, that the transmitting device may emit and stilloperate within FCC limits. These calculated values may be included inyet another column associate with the table. This last column would beused by a transmitting UWB wireless device 31 to adjust the amplitudeassociated with each OFDM frequency bin on a per-bin basis. As will beappreciated by those skilled in the art, this may be done relativelyeasily with OFDM since the modulation starts in the frequency domain atthe transmitter prior to the transmission inverse FFT (IFFT) thatresults in a time waveform for transmission.

Another UWB wireless communications method aspect of the invention forsetting the transmission power level as described above is now describedwith reference to FIG. 12. Beginning at Block 120, a plurality of UWBwireless devices 31 a′-31 n′ communicate over a plurality of UWBfrequency bins extending over a UWB frequency range, at Block 121, asdiscussed above. An existing interference level associated with at leastone of the UWB frequency bins is determined, at Block 122. Further, adesired transmission level is set for use with the at least one UWBfrequency bin based upon the existing interference level to keep apredicted overall interference level of the at least one UWB frequencybin below an interference ceiling, at Block 123, as further discussedabove, thus concluding the illustrated method (Block 124).

Additional method aspects will be further understood with reference toFIG. 13. In particular, prior to determining the interference noisetemperature, it may first be determined whether the particular device isengaged in communications, at Block 130′. If so, the device waits untilthe communications have ceased, and then it begins the interferencenoise temperature determination. This includes determining a pluralityof successive signal levels for one or more of the bins (Block 131′),generating a histogram for each frequency bin based upon thesuccessively determined signal levels (Block 132′), and determining theinterference noise floor based upon the histogram (Block 133′), asdiscussed above.

The existing interference noise temperature may then be determined usingthe interference noise floor, and the gain and noise level associatedwith the device 31 a′, at Block 134′, and the desired transmission levelmay then be set accordingly for the bin(s), at Block 123′, as describedfurther above. The desired transmission levels, which may be embodied ina table as described above, may then be communicated to one or moreother devices 31′ for use in communications therebetween, at Block 135′.

By way of example, the various aspects of the present inventiondescribed above are particularly well suited for products or devicesused in wireless PANs with relatively short range (e.g., less than 10meters) and high bit rates (e.g., greater than 100 Mbps). Although theinvention has generally been described in the context of the proposedIEEE802.15.3 and 3a standards for clarity of explanation, it may be usedin other UWB communications applications as well, as will be appreciatedby those skilled in the art.

Many modifications and other embodiments of the invention will come tothe mind of one skilled in the art having the benefit of the teachingspresented in the foregoing descriptions and the associated drawings.Therefore, it is understood that the invention is not to be limited tothe specific embodiments disclosed, and that modifications andembodiments are intended to be included within the scope of the appendedclaims.

1. An ultra wideband (UWB) wireless network comprising: a plurality of UWB wireless devices communicating over a plurality of UWB frequency bins extending over a UWB frequency range; at least one of said UWB wireless devices for determining an existing interference level associated with at least one of the UWB frequency bins, and setting a desired transmission level for use with the at least one UWB frequency bin based upon the existing interference level to keep a predicted overall interference level of the at least one UWB frequency bin below an interference ceiling.
 2. The UWB wireless network of claim 1 wherein the existing interference level comprises an existing interference noise temperature level, and wherein the interference ceiling comprises an interference noise temperature ceiling.
 3. The UWB wireless network of claim 2 wherein said at least one UWB wireless device determines the existing interference noise temperature level by: determining a plurality of successive signal levels associated with the at least one UWB frequency bin; determining an interference noise floor based upon the successively determined signal levels; and determining the interference noise temperature level based upon the interference noise floor.
 4. The UWB wireless network of claim 3 wherein said at least one UWB wireless device determines the interference noise floor by: generating a histogram based upon the successively determined signal levels; and determining the interference noise floor based upon the histogram.
 5. The UWB wireless network of claim 3 wherein said at least one UWB wireless device has a gain level and a noise level associated therewith; and wherein said at least one UWB wireless device determines the existing interference noise temperature level based upon the interference noise floor and the gain and noise levels associated with said at least one UWB wireless device.
 6. The UWB wireless network of claim 3 wherein said at least one UWB wireless device comprises a fast Fourier transform (FFT) module for determining the successive signal levels.
 7. The UWB wireless network of claim 3 wherein said at least one UWB wireless device comprises a discrete Fourier transform (DFT) module for determining the actual signal levels.
 8. The UWB wireless network of claim 1 wherein said at least one UWB wireless device communicates the desired transmission level to another UWB wireless device for use in communications therewith.
 9. The UWB wireless network of claim 1 wherein said at least one UWB wireless device determines the existing interference level when it is not communicating with another UWB wireless device.
 10. The UWB wireless network of claim 1 wherein the UWB frequency bins comprise orthogonal frequency division multiplexing (OFDM) frequency bins.
 11. The UWB wireless network of claim 1 wherein said at least one UWB wireless device performs frequency hopping.
 12. A ultra wideband (UWB) wireless network comprising: a plurality of UWB wireless devices communicating over a plurality of UWB orthogonal frequency division multiplexing (OFDM) bins extending over a UWB frequency range; at least one of said UWB wireless devices for determining an existing interference noise temperature level associated with at least one of the OFDM frequency bins, and setting a desired transmission level for use with the at least one OFDM frequency bin based upon the existing interference noise temperature level to keep a predicted overall interference noise temperature level of the at least one OFDM frequency bin below an interference noise temperature ceiling.
 13. The UWB wireless network of claim 12 wherein said at least one UWB wireless device determines the existing interference noise temperature level by: determining a plurality of successive signal levels associated with the at least one OFDM frequency bin; determining an interference noise floor based upon the successively determined signal levels; and determining the interference noise temperature level based upon the interference noise floor.
 14. The UWB wireless network of claim 13 wherein determining the interference noise floor comprises: generating a histogram based upon the successively determined signal levels; and determining the interference noise floor based upon the histogram.
 15. The UWB wireless network of claim 13 wherein said at least one UWB wireless device has a gain level and a noise level associated therewith; and wherein said at least one UWB wireless device determines the existing interference noise temperature level based upon the interference noise floor and the gain and noise levels associated with said at least one UWB wireless device.
 16. The UWB wireless network of claim 13 wherein said at least one UWB wireless device comprises a fast Fourier transform (FFT) module for determining the successive signal levels.
 17. The UWB wireless network of claim 13 wherein said at least one UWB wireless device comprises a discrete Fourier transform (DFT) module for determining the actual signal levels.
 18. The UWB wireless network of claim 12 wherein said at least one UWB wireless device communicates the desired transmission level to another UWB wireless device for use in communications therewith.
 19. The UWB wireless network of claim 12 wherein said at least one UWB wireless device determines the existing interference noise temperature level when it is not communicating with another UWB wireless device.
 20. The UWB wireless network of claim 12 wherein said at least one UWB wireless device performs frequency hopping.
 21. A ultra wideband (UWB) wireless device comprising: a UWB transceiver for communicating with at least one other UWB wireless device over a plurality of UWB frequency bins extending over a UWB frequency range; a controller coupled to said UWB transceiver for determining an existing interference level associated with at least one of the UWB frequency bins, and setting a desired transmission level for use with the at least one UWB frequency bin based upon the existing interference level to keep a predicted overall interference level of the at least one UWB frequency bin below an interference ceiling.
 22. The UWB wireless device of claim 21 wherein the existing interference level comprises an existing interference noise temperature level, and wherein the interference ceiling comprises an interference noise temperature ceiling.
 23. The UWB wireless device of claim 22 wherein said controller determines the existing interference noise temperature level by: determining a plurality of successive signal levels associated with the at least one frequency bin; determining an interference noise floor based upon the successively determined signal levels; and determining the interference noise temperature level based upon the interference noise floor.
 24. The UWB wireless device of claim 23 wherein said controller determines the interference noise floor by: generating a histogram based upon the successively determined signal levels; and determining the interference noise floor based upon the histogram.
 25. The UWB wireless device of claim 23 wherein said UWB transceiver has a gain level and a noise level associated therewith; and wherein said controller determines the existing interference noise temperature level based upon the interference noise floor and the gain and noise levels associated with said UWB transceiver.
 26. The UWB wireless device of claim 23 wherein said controller comprises a fast Fourier transform (FFT) module for determining the successive signal levels.
 27. The UWB wireless device of claim 23 wherein said controller comprises a discrete Fourier transform (DFT) module for determining the actual signal levels.
 28. The UWB wireless device of claim 21 wherein said controller cooperates with said UWB transceiver to communicate the desired transmission level to another UWB wireless device for use in communications therewith.
 29. The UWB wireless device of claim 21 wherein said controller determines the existing interference level when said UWB transceiver is not communicating with another UWB wireless device.
 30. The UWB wireless device of claim 21 wherein the frequency bins comprise orthogonal frequency division multiplexing (OFDM) frequency bins.
 31. The UWB wireless device of claim 21 wherein said controller cooperates with said UWB transceiver to perform frequency hopping.
 32. A ultra wideband (UWB) wireless communications method comprising: using a plurality of UWB wireless devices to communicate over a plurality of UWB frequency bins extending over a UWB frequency range; determining an existing interference level associated with at least one of the UWB frequency bins, and setting a desired transmission level for use with the at least one UWB frequency bin based upon the existing interference level to keep a predicted overall interference level of the at least one UWB frequency bin below an interference ceiling.
 33. The method of claim 32 wherein the existing interference level comprises an existing interference noise temperature level, and wherein the interference ceiling comprises an interference noise temperature ceiling.
 34. The method of claim 33 wherein determining the existing interference noise temperature level comprises: determining a plurality of successive signal levels associated with the at least one UWB frequency bin; determining an interference noise floor based upon the successively determined signal levels; and determining the interference noise temperature level based upon the interference noise floor.
 35. The method of claim 34 wherein determining the interference noise floor comprises: generating a histogram based upon the successively determined signal levels; and determining the interference noise floor based upon the histogram.
 36. The method of claim 34 wherein determining the successive signal levels comprises determining the successive signal levels using a fast Fourier transform (FFT) module.
 37. The method of claim 34 wherein determining the successive signal levels comprises determining the successive signal levels using a discrete Fourier transform (DFT) module.
 38. The method of claim 32 wherein the UWB frequency bins comprise orthogonal frequency division multiplexing (OFDM) frequency bins. 